The images lend themselves to heat embossing so that is exactly what I have done, I've deliberately left them a bit plain as I thought too many embellishments would distract from the design. I've also used different embossing powders on them, the first one I tried "brass" from WOW, and the second is using "pewter" from stampin up then I tried liquid platinum and silver from ranger, not sure which one I prefer.
Image: "freebie" from papercraft essentials magazine
Sentiment: "grand holiday greetings" MFT
Dies: Blueprints 20 and 13
Card: "real red" stampin up and "jellybean green" MFT
Embossing powder: "pewter" stampin up and "metallic brass" WOW